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I just got a hot air soldering station and was practicing on some old PC boards and was wondering what temperature is best to remove and replace the PCM1804 chip. In my practice it seems that around 700F will be best for removal and probably something lower for soldering the chip in place.?

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What do you guys think?

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Myron WV0H

Hi Bob,

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I once heard FT8 tone on 14.100 and I did a factory reset, it fixed the problem. Set VFO A=B is also worth to try.

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72, Wei

I just completed the build for my new QMX+ , rev 1, firmware .27. The QMX + is a fantastic transceiver.

I am really impressed. Hans has done a wonderful design.?
I was tuning across low end of 40 meter band and came across W1AW code practice session

on 7.0475 MHz. Tuning further up in frequency at 7.073 MHz I found W1AW again. Very unusual.?
why? ?So exploring I fed in bnc connector a low level RF signal from my signal generator at 7.0475 MHz

and heard it also at 7.073 MHz. I wonder if this comes from mixer math?

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Has anyone also seen this?

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Thanks for any input. ?
Bob, K3TCT

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On Thu, Oct 3, 2024 at 08:00 PM, Hans Summers wrote:

I think this would be quite feasible and not particularly more difficult than the APRS message for map tracking. If you know what the right?APRS sentence for self-spotting is? Any info on this???

I don't know for sure as when I do portable activations, I don't carry with me a computer...

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Nevertheless, I know for sure firstly that if you adress a JS8Call message to APRSIS (JS8 message starting by @APRSIS) and include after a corrected formatted APRS message, it gets into the APRS system and secondly that there are APRS gateways to selfspot a POTA or SOTA activation. I vaguely remember seeing a video of somebody managing this.

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If you want I can have a go at doing it with a computer and my QMX and report back when I understand better how it works.

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If you want to play with F1ZXO, you are more than welcome.... it was initially powered by a QDX and a raspberry Pi but the finals got damaged by an antenna with varying SWR, the QDX is on my bench right now and hopefully it will be back in service sometimes in the future, the QMX with its SWR protection would have been better but it didn't exist at the time we bought the TRX. We are now only servicing 40m, but the band hopping is not abandoned and hopefully will be back soon.?

As for the difficulty to decode, I am not that surprised by your reply, decoding is indeed hard on the computer/microcontroler...

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73,

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Yannig - F4IUJ

I found a nice narrow band external signal from some nearby device like a power supply to compare between the filter options. I looked at the IQ output and there really doesn't seem to be much difference in SNR between digi and CW with even the 150hz filter, so that's good. It still sounds muddy / flat through that filter most of the time though. I'm going to have to try moving then center / offset around. This may be a function of the response of the headphones that I'm using or something subtle way at the end of the audio processing and output chain.

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Greg N1TR

While I've not had a chance to try it yet it would seem that RTTY

should work just fine.? Its one of two single tones and a Arduino?

can easily decode them.? Add to that its a conversational mode.

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Its not as noise resistant as JS8call but that's a trade for greater speed.

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Allison
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Post online only,?
direct email will go to a bit bucket.

On Thu, Oct 3, 2024 at 01:01 AM, Hans Summers wrote:

Hello Barry

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Where would I find more info on "The SteppIR controller".

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Specifically, it's this part:?

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73 Hans G0UPL

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TU Hans

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I was hoping it may be a replacement for the Fluidmotion. One can always hope.

Cheers mate es TU for wonderful kits.

Hi
Now I prefer to use QMX+ LPFs and BPFs

I used the 6m setup from QMX+ on QDX-M
worked beautifully
73 DE muhsin TA1MHS

Hi Hans,

This link covers spotting SOTA via APRS,

Another option is Sotamat, it uses the suffix on you callsign sent via FT8. The suffix is converted to a SOTA or POTA spot by a look up table in the Sotamat system. I am yet to test it via JS8, but the information with the app states it's not stuck to FT8 but any digital mode that PSK Reporter does not strip the Suffix from call signs should work, e.g. RTTY, PSK and maybe others. Sotamat will also send pre-programed SMS's and Email via the same lookup table system.

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73,

Warren

On Thu, Oct 3, 2024 at 06:22 AM, Ronan Cantwell wrote:

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the chip body is just that tiny bit too long for the available space without modification.

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Highly recommended

JS8Call from A-Z Covering the Basics to Advanced Settings In One Video

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I agree, muhsin, and I'm very pleased to find that KW3KW is still making videos! IIRC, several months ago he announced in a video that he was fighting health problems and he didn't know how long he could keep producing them.

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I intend to finish watching all of his JS8 videos:

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73,

Cal -- AD8Q

Hello Hans,

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Thank you,

Tony AC9QY

1st make sure Vdd and Vcc at JP105 are not shorted to ground.

2nd make sure you have 12v on JP105 while pressing the power button.

3rd then look to see if you also have 12V at input pin to IC101 (3.3v reg.) while pressing the power button.

If not, check the Drain on Q101. It should be 12v when the power is NOT pressed and 0V while power button is pressed.

If it does then I would think Q102 is bad.

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It looks like if you don't get 3.3V from the regulator (IC101) while pressing power button, the processor wont start and control the 2 plug in power supplies.

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-Steve

Eddie,

?I agree that repairing the SMPSs is probably not a good idea. My first QMX (rev 1) kit failed with an exploding tantalum cap on the 5V SMPS. Initial tests on the repaired unit looked good and the unit powered up fine, but a few minutes later IC401 failed and the radio shut down. I was warned to get new SMPSs, which were just coming out on QRP Labs' site.?

Good thing I listened, as later tests showed serious problems with my repaired boards. Fortunately the IC401 was the only casualty from the initial use of my repaired SMPSs.?

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73, Dan? NM3A

On Mon, Sep 30, 2024 at 10:52 AM, Hans Summers wrote:

What Warren is suggesting is standalone support for sending the correct JS8 messages that can be used for tracking purposes. In this use of JS8, an appropriate message is transmitted which activates the JS8 -> APRS gateway then the tracking point shows up on . In this mode you would be able to set QMX (say) in a location tracking mode and it would periodically extract its position from a connected GPS, and send the APRS?message via JS8. Any receiving stations then log this to APRS.?

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I think it's a nice idea and I am also interested in this. I have added it to my list but it will not be highest priority yet.?

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That would be fantastic Hans... I think this would be a really cool addition to the QMX, and once the most important things are sorted, I would also be keen to see this improvement.

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While you are at it, it would be nice to also allow SOTA/POTA selfspotting via APRS. The idea would be that you would just need to adjust the clock, enter your SOTA/POTA summit number, your QRG / mode and the QMX would then send the right APRS sentence via JS8 to self spot.? That would be really useful for activations without cellphone coverage.

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My club is keeping on the air 24/7 (when things go right!) a JS8Call station : so that people can use it as a mailbox. I realise this is a lot more work for you as on top of coding to JS8 you would need to sort out the decoding, but it would be very nice if a QMX could be used to send / receive messages to a 24/7 JS8 station. We are not the only ones, there are quite a few 24/7 stations around and some kind of rudimentary "communication through mailbox" would become possible.

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73,

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Yannig - F4IUJ

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I just finished building my QMX+ and had the same problem. I found that I did not set the VBAT to Vdd jumper wire close enough to the board under the GPS board and it shorted out the Vdd to the SMA connector.

After removing the GPS board, the short went away but Vdd was dead. Q102 was now bad and after replacing it, everything powered up.

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-Steve

How is the time set with the RTC??

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Don

W6CZ

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I'd personally not try to repair that SMPS for possible use except for rework practice and then run the standalone tests to see if I succeeded.

Greg